C++ Language

Memory

• [[clflush]]

Tips

String

• 문자열 관련해서 사용하기 쉬운 함수들

#define TRIM_SPACE "\t\n\v "
vector<string> split(string input, char delimiter) {
  vector<string> answer;
  stringstream ss(input);
  string temp;

  while (getline(ss, temp, delimiter)) {
    answer.push_back(temp);
  }
  return answer;
}

string trim(string& s, const string& drop = TRIM_SPACE) {
  string r = s.erase(s.find_last_not_of(drop) + 1);
  return r.erase(0, r.find_first_not_of(drop));
}

Time

• 시간 잴때 사용하는 코드 더미

• minuk.h

  #ifndef __MINUK_H__
  #define __MINUK_H__
  #include <time.h>
  unsigned long long calclock(struct timespec *spclock, unsigned long long *total_time, unsigned long long *total_count);
  #ifndef BILLION
  #define BILLION 1000000000
  #endif /* BILLION */
  #endif /* __MINUK_H__ */

• minuk.cc

  #include "minuk.h"
  unsigned long long calclock(struct timespec *spclock, unsigned long long *total_time, unsigned long long *total_count){
    long temp, temp_n;
    unsigned long long timedelay = 0;
    if (spclock[1].tv_nsec >= spclock[0].tv_nsec) {
      temp = spclock[1].tv_sec - spclock[0].tv_sec;
      temp_n = spclock[1].tv_nsec - spclock[0].tv_nsec;
      timedelay = BILLION * temp + temp_n;
    } else {
      temp = spclock[1].tv_sec - spclock[0].tv_sec - 1;
      temp_n = BILLION + spclock[1].tv_nsec - spclock[0].tv_nsec;
      timedelay = BILLION * temp + temp_n;
    }
  
    __sync_fetch_and_add(total_time, timedelay);
    __sync_fetch_and_add(total_count, 1);
    return timedelay;
  }
  
  /**
   * example code
   *
   * struct timespec spclock[2];
   * clock_gettime(CLOCK_REALTIME, &spclock[0]);
   * do something
   * clock_gettime(CLOCK_REALTIME, &spclock[1]);
   * calclock(spclock, &total_time, &total_count);
   *
   * */

Books

• [[Modern C++ Design Pattern]]